TPCA-1 is a selective inhibitor of IκB kinase-2 (IC50s = 17.9 nM and 0.40 μM for IKK2 and IKK1, respectively). Furthermore, it displays greater than 550-fold selectivity over other kinases and enzymes including, p38, MAPK, COX, and JNK. TPCA-1 inhibits the production of LPS-induced TNF-α, IL-6, and IL-8 with IC50 values equal to 0.17, 0.29, and 0.32 μM, respectively. At 20 mg/kg, TPCA-1 has been used to reduce the severity and onset of collagen-induced arthritis in mice and at 30 mg/kg to block cytokine release in an antigen-driven rat model of lung inflammation.
